There is no upper toxic level for B12.

You can look that up on any valid site.

On the first post of the B12 thread on
the PN forum is a link to a study published
by a doctor demonstrating 13 mcg are absorbed
from a 1000mcg oral dose. This is hardly
An alarming amount. Also on that table of
that paper is that a 1000mcg injection
results in only 150mcg measured in the
Serum.

You can copy that and give it to your
Doctor.

The only contraindication I have seen
is to not use B12 in patients with polycythemia
Vera which is a rare blood disease and
would show up in your testing so far. It
results in too many red blood cells.

Responding to Dr. Smith

When I was first diagnosed about 10-11 years ago I was taking Prevacid for a few weeks then I just stopped. When I had occasional flare ups I would buy OTC products. I didn't take anything for a long period of time. I was also heavy on popping Ibuprofen whenever I felt pain, I constantly took alleve or excedrin for my frequent headaches.

If you've been DXed with peptic ulcer, you've been taking the wrong things—ulcers can be caused/exacerbated by meds like aspirin, ibuprofen, and naproxen. I gave myself a bad case of IBS by taking too much ibuprofen, and nearly lost half my bowel. Hopefully, you can find a gastroenterologist that will work with you to find a better treatment/cure, taking your PN into account.

Because of my IBS, I only use acetaminophen. Due to its harshness on the liver, I also take N-acetylcysteine (NAC) to reduce/negate that effect. I get tested regularly, and my liver is fine.

Some of those other meds can also cause rebound headaches. If your headaches are something else (e.g. migraine, cluster, et al), you might consider seeing a headache specialist (practice limited solely to headache/migraine—not just a run-of-the-mill neurologist). I suffered from two types of chronic headaches for years before finding a good headache guy who knew his stuff.

Doc